Automatic ratchet wrench



DCC. 22, 1931. J, C, HQCHMAN 1,837,819

AUTOMATIC RATCHET WRENCH Original Filed Jan. 30, 1922 2 Sheets-snee?l l ff" u Z9! a?? /NVENTOR Jzdz'af Lm/2mal?,

' ATTORNEY Dec. 22, 1931. J. c. HocHMAN AUTOMATI C RATCHET WRENCH Original Filed Jan. 30, 1922 2 Sheets-Sheet 2 [N VENTOR Jil/im' (Z500/2112072 A TTORNEY Patented Dee. 22, 1931 Parleur @FFICE JULIUS C. HOGHMAN, 0F NEW YORK, N. Y.

AUTOMATIC WRENCH Grig'inal application filed January 30,1922, SerialNo. 532,571. Patent No.y 1,794,614, dated March 3, 1931. Divided and this application filed February 1'?, i931. Serial o. 516,484.

T his application is a division of my parent application for releasable screw mechanism, Seria-l No. 532,571, filed J an. 30,' 1.922, now

issued as Patent Number 1,794,614 dated March 3, 1931, which discloses my invention as applied to a variety of screw actuated or screw locked devices.

In the present disclosure, I show and claim my releasabl embodied in a monkey wrench for controlling the lock and releasing of the jaw-locking screw element or worm,`now commonly employed for hand adjustment. It will be obvious, however, thatV the same mechanism may be used wherever such a screw lock and releasev is desired; also that certain of its broadly novel principles and features may be embodied in other devices where it is desired for the operation or control of any screw-actuated, screw-loaded, or screwlocked member, for automatic lock or automatic release thereof, and particularly for quick sliding adjustments with automatic screw-lock and -release y In applying the invention to monkey wrenches of various designs I have found it possible and highly desirable to retain the ordinary screwing adjustability, as well as the outward appearance, structure, and proportioning popularly recognized as characteristic of a monkey wrench; including, in one type the fixed jaw and a shank on which the sliding jaw slides, said shank having the usual rack and said sliding jaw having associated with it the adjusting worm or nut which (3o-operates with the rack; and, while preserving these within limits, I associate them with other mechanisms including a pilot screw element whereby the locking screw element may be automatically rotated to permit free sliding movements of the movable j aw in one or the other or both directions, as

may be desired; these elements being organized for the purpose and with the result that the slidiiw 'aw ma be arranged to onen orf D :D a

to close in response to endwise pressures, or to be automatically locked against said pressures in either desired one of said directions. Preferably, also there is an element, ypreferably a spring, whereby the sliding aw is locking-screw mechanism as pressed toward the fixed jaw, preferably with sufficientpower to give automatic closing of the jaws, though it may be mere balancing of the weight and friction of the sliding jaw; and in other embodiments I may utilize gravity inV place of a spring, either as a balance or as a counter-balance.

In a preferred type of monkey wrench the rotary locking screw element, the longitudinalrack to which it is threaded, the sliding jaw and the pilot screw element are all so organized that a slight angular movement of the handle of the monkey wrench when applyingpressure to screw a nut or bolt in the desired direction, will operate to throw the parts into locking relation, while reversed pressure on the handle will release the locking element and put the pilot screw element in the automatic screwing relation to said locking element, preferably by imparting slight endwise movement to the pilot screw element. The locking direction for the pressure is preferably reversible by a simple adjustment; and in both directions, the

` locking movementbrings the handle into solid Contact with the shank, thereby rej lieving its pivotal centre of all strain.`

Thus by my invention'the Lmonkey wrench becomes capable of operation as an automatic ratchetwrench, the jaws of which will open freely to rotate around the corners of a nut when pressure is applied to the handle in one direction, will close automatically, and will be automatically locked when pressure is applied to the handle in the opposite direction. Similarly, the sliding jaw will slide open under hand pressure for application to the nut or bolt, when the handle is in the first position, and will automatically close, and will lock when the handle shifts under the reverse pressure.

For these purposes,=the pitch and areas of the locking screw threads and other thrustbearing surfaces of the rotating element are such as to afford prohibitive frictional opposition to any automatic screwing in response to the endwise thrusts or pressures applied eitherto said sliding jaw through said locking thread or to said locking thread through said sliding jaw; and the pilot screw element engaging the locking screw element is of the same pitch as the locking screw thread but on a radius so much smaller that the pitch angle of pilot thread is a slipping angle, preferably an angle offvery easy slip.

By slight. endwise displacement of either oneV of the screw elements in the direction of an endwise applied thrust, the endwise load may be shifted from one screw elementlto the other with resultant endwise slip or endwise lock, according to which thread is. caused to take the load. A. very simple machine element such as a cam or lever may be employed to cause the required endwise shift and the operation of such machine element may beV controlled manually or automatically in a gr-eat variety of ways. ln the monkey wrench, the shift ofload occurs just after the instant of substantially no-'load when the pressure on the handle is reversed; so ythat when the new (reverse-screwing) load comes,.

pitch of the locking threads andthe slip threads is precisely the saine. Hence the only loadthat can ever come lon the pilot screw is the free worms frictional resistance to rotation and this resistance may be made practically negligible. AHence the pilot screw may be very'light.

Vith these basic elements, itis possible to combinel many specifically dilferent means for relative movement ofthe pilot screw with reference to the locking screw whereby'tlie threadsof the latter may be slightly rotated orrotherwise moved outof lockingifrictional contact with the rack teeth or other relative:

stationary locking rack or screw element.

The essential is that the worin become free ofv rotation and worming along the rack during, and because of, and at the rate compelled by the' worins endwise movement along the slip angle groove of said pilot screw element. The' releaserof the frictional loclniay be complete or partialfas may be desired and thefdegree of frictional contact may be held absolutely constant for any period of time.

Considered more specifically in some respects, and in others'inore broadly, my invention may be viewed as including. a lock screw element havingco-axial threaded rela-l tion with two other screw eleinentshaving theV same number of `turns per unit length but dirferent pitch diameters, such that the engagement between the threads of greater di-v ameter iseither at a non-slip angle or in any and will control when said elements aie slightlyde-phased in one direction or the other, and whereby, when said elements are precisely in phase, the slip angle thread will translate the load thrust into desired relative movements of certain of the parts.- For most purposes it is desirable to have the clearance, or 'looseness of lit for the largerdiameter, locking-angle threads, greater than for the smaller-diameter, slip-angle threads. lt is conceivable that for some pui'- poses this relation of clearances might be reversed. Such reversal would be useful with reference to theV broad novelty of my combination considered as a new mechanical movement, for instance, where power is applied to the rotary lock screw element for the purpose of producingor preventing certain Adesired movements of the slip angle screw element.

Considered as a novel mechanical movement usable for translatingthrusts or rotating 'efforts applied to any one of the three elements with the view to producing resultant stresses, movements or locking effects on any oth er of said elements, the invention may be considered morebroadly as a screw element threaded to two other screw elements having the same rate ofscrew feed, .preferably by rhavingthe same number of threads per unitlengtlnrbut having different pitch diameters so that their stresser motion producing resultants are different. Changing the method of control will make it possible tocause the locking screw to be variously affected, but in the present wrench, the sliding aw is free to follow or obey any longitudinal external force, except when the wrench is exertingcturning moment on the nut in the direction selected. The-effect of this is to allow free ratcheting when theV vtional Alock as governed and maintained by the-positively controlled pilot mechanism.

IVR

While thev locking screw thread and the 1oilot screw or slipping thread may be formed on separate elements, they may be made in a torin wherein there is a single deeply-cut threaded screw, the outer or larger diameter peripheral portion of which presents a positive locking angle while the innermost part et the groove is steep enough to give an angle ot easy slip. ln this case two other screw elements are employed, one having threads adapted to eneage the outer part of the groove, the part that has the locking angle, while the other engages 'only the innermost pai-t ot the groove, the part that haslthe slip ai gle. v

ln Jthe terms shown herein the threads of the locking screw elem-ents are preferably l to have much more clearance or loosei ess ot titthan are the slip-angle threads,

but this is to avoid the necessity for great accuracy in the endwise shift to malte one thread or the other take the load. However, either thread can be made to take the load even when the clearance is very small when the slip thread clearance'is greater than the loch thread clearance. the forms shown herein, it is the pilot screw element that is preterably given the endwise shift with reference to the locking screw ele- :nent in order to tree the locking threads trom locking engagement, bringthem to an intermediate position, meshingr with, but time troni, the teeth of the rack, or equivascrew element, but it will be understood shift of the relative positions ot the y"is, the functionally important feature,

the matter of which element moves to g about the sliitt has to do with the: more Decine aspects the invention. n

ls'betore intimated, the shift ot control from the locking thread to the slip thread ma7 be only partial or may be momentary. rlhis may be especially desirable under certain conditions as where there is a gravity load on the locking thread and it is desired to lower the load slowly or to a predeter-Y mined distance only. In such case special neans n i., be provided tor agradual or i nl yraasiei o, some or 4ne ioar to ne slip thread element. In such operation, the torque and thrust stresseson the slip thread may be considerable and tne pilot screw elementhas to be oit correspondingly heavier corftrnc fion.

ary'teature ot my invention. rlhis contemfilates .makingV the worm with its locking ds and the pilot threads capable ot' movement longitudinally but This may be accomtiallv.

y forming the respective threads on -iial 1dreterabl f concentric sleeves that and practical applications ot nated by utilizing an important sub-l are connected by a spline. Then, it desired, thel pilot sleeve element may be provided with anti-friction thrust-bearings, thereby minimizing the said sleeves trictional resistance to rotation under load, the factor upon which depend the load-taking capability and resulting` stress on the pilot screw. The spline connection also leaves the sliding jaw and the inner pilot. sleeve tree for a slight endwise movement with respect to the outer locking sleeve, when the pilot screw rotates the locking thread into and out ot locking engagement with the rack teeth. Upon. locking, this permits the end thrust of the full load to be applied by the sliding` jaw. to the end ot the locking sleeve and through the locking thread to the raclr, without endwise stress upon the inner sleeve or its endwise thrust-bearing; and upon unlocking, the effect is to immediately permit the outer sleeve to tall free from its endt` 1 ust engagement with the sliding aw.

it will be noted that my mechanism in cludes inter-engaging elements capable ot solid locking under thrust by frictional engagement with each other, in combination -with co-acting mechanism controlling the loclr by positively controlling said trictional contact.

lt will also be `noted that the locking elements and the pilot `elements consti-nte respectively primary and secondary sets of mechanical transmission elements, the motion transtorming ratios ot which areiixed and arel the saine; thatthe primary elements lock under load while the secondary ele-- ments are idle.; that the secondary eleme tend to rotate under load; that tieload n iy be shifted to the secondary elements; and finally that the two sets ot elements are so coupled` that rotation ot the secondary sel under load will cause unlocking and rotation ot th-e primary set.

The above and other features of my novel meci anical movement, as well as a variety of special applications thereof, may be more fully understood from the following description in connection with the accompanying drawings, in which `l is a side elevation of one form oie inonliey wrench having one form of my invention applied thereto and with the lockingv screw element in the locking position.

Fig. 2 is a vertical sectional elevation Vof the same mechanism with the pilot screw element operating and the locking scew element tree. V

3 is a section on the line 3 3, showing thY shape of the groove ot the pilot screw.

li, 5, 6 and 7 are detailed views showing various positions of a simple term ot cam employed to shift the pilot screw to unlock the locking screw.

Fig. 8 is a vertical sectional view similar pea to-Fig. 2, but/showing af modification of my invention as applied to another well-known .groove 12 so that sleeve o i loclred form or" monkey wrench. Y

Figs. 9 and 10 are, respectively, end View and side elevation of the sliding jaw shown in Fig. 8.

Fig. 11 is a vertical sectional view showing another modification of my invention applied to another type of wrench.

Fig. 12 is a detail elevation of parts shown in Fig. 11, loolringfrom the left.

Fig. 13

iteferring to TFigs. 1 and 2 of the drawings,

Y ckingthread adapted for rotation l udinal screwing movement in mesh, no` necessarily in engagement, with the ich in this caseV is a rack, the raclr being, functionally considered, a narrow segment of a female crew thread. The loch-ing thread 1 is formed on a sleeve 3 which is rotatably mounted in and carried by the aw d, being, in this case, locate-d in a rrecess between the thrust surface lo and the bracket member ad. rEhe jaw loop portions ila, 41. rl`he co-operating )aw f3 is rigid with shank 5. A

Though the significant movements and stresses are all relative, it is convenient, for descriptive purposes, to consider the jaw 6', shank and raclr-2fas lined and otherV parts as movable with reference thereto; and, al-

"though theworlring pressures on jawsll and 5 are equal and opposite, the manipulating pressures are on one jaw only, and it is convenient to consider the sliding jaw l as the load carrying member..r

rllhe pilot screw 7 has a pilot threadin the forni gag-ement .with'tlie interior projecting-lugs or` thread elements 9. Said interior thread elements 9 may be formed directly'on the interior of the sleeve 3 which has loch-ing. thread on the exterior thereof. Preferably, however. said threads 9 are 1n a separate sleeve is free for slight movement longitudinally but is to sleeve 10i-so lfar as concerns rotary movement. y n

The pilot thread 3 hasl the same number of turns per inch as locking thread 1, but the pitch is steep enough to permit easy slip and rotation of one of the pilot elements 7 or 9, by

the other, in response to endwise pressure of either or both with resp-ectfto the-other. .ln

f the present casethe pilot screw is non-rotatable with respect to jaws l and G and vshank 5, so that sleeves 19 and 3 and locking thread 1 carried by thelatter, are the elements that rotate when there is relative longi# 5 tudinal movement. f

isa section on the line 13-13 of stationary locking screw elementv l has sliding engagement with shank 5 to which it issuitably secured by strap or of a groove 3 which' is in threaded 'en-- nnber 19 which is s )lined to' loclrinfr sleeve j. C o by means or screw 1i. tted into a splinev Vexertsupward pressure on sliding jaw l Whether the locking thread` or the pilot thread will control will depend on whether or not the pilot screw 7 is endwise supportedk Y threads 1 to the rack teeth 2 and through them to sham; and co-operating jaw 6.

When the pilot screw .7 is longitudinally supported in the upper position, a load applied on jaw l in the direction of arrow X will not be supported by the slip angle groovev 3, and Ll will move downward along the pilot screw and the locking screw threads 1 will not thereby engage'and lock against rack 2f, because said longitudinal movement will rotate the locking worm thread 1 at exactly the required rate to leeplsaid thread 1 out of frictional loch engagement'with the teeth of rack 2. Moreovenwhen the pilot screw 7 is deprived of its endwise support, the locking threads 1 will immediately engagev the teeth 'of raclr 2v and will lock the aw l against further retreat. Hence, inorder to have the sliding jaw either free or locked at will, it is only necessary to give the pilot screw 7 a Y slight endwise shift.

ris-shown inl the drawings, `this is accompllshed by providing the lower part of shank 5 with a handlel member preferably inr the form of a light sheet metal casing 13, pivoted on bolt-.14 and carrying ,a suitable cam surface 15, in position whereit will apply endwise thrust and'sup-port upon said pilot screw 7 when the handle swings in one direction as forthe screwingr pressure; and will Vremove said thrust and support when the pressure is Vpin 2O extending through the lower end of theVV pilot screw 7 The pilot screw7 is normally `hrust downward against cam surface by means of an encircling spring 21, which,

at oneA end, engages collar 22 on screw 7 andat the other-end, an inwardly extending annulus 23 of nipple 24, which latter is screwthreaded in bracket ed.' The spring 21 thus whereby the aws will automatically close when unlocked from the rack 2.

The cam surface 15 may be adorded by a stud-member 25, `mounted in an end piece 28, secured by cross boltsor rivets 27 in the bottom of handle 13.V vThis cam stud is made rotatable so that it can be held in any one of several positions by means of locking. screw 23 engaging one orthe other of recesses 29,29, 30a, 31a'. (See Figs. l to 7, inclusive.) As shown in Fig. 2, the screw 28 `engages recess 311, and in this position,`applying trans- Vin the position shown in Fig. 1.

i ation, the sliding jaw l is `entirely unlocked and may be moved freely in either direction, with or against the pressure of spring 21. It may be retained against said pressure by a finger or thumb of the user engaging lugs 4e or 4f, which are provided for this purpose.

lt should be noted that these lugs'may also be used for slidably opening thejaws, with a linger or thumb of the. hand holding the wrench, thus adapting the wrench for comf plete one-hand operation.

Vflien thc `direction of pressure on handle 13 is reversed, however, the handle will come in solid contactwith surface 30 of shank 5,

v In this 'position, the cam surface 15 permits retreatyof pilot screw Z under the influence of spring 21 with the result that the locking thread l immediately7 engages rack teeth 2, as shown in said Fig. 1.

This results in a monkey wrench wherein pressure applied to the handle toward the leftv` will lock the sliding jaw has shown in Fig. 1, while pressure toward the right will release the sliding jaw, as shown in Fig. 2. Thus the jaws will automatically Vratchet around .the head of a bolt or nut in response to the screwing and resetting pressures. The lighter the spring 2l, the lighter will be the ratcheting stress, but the slower will be the reseating ofthe jaws; but in general a light spring is desirable and in practice its lightness will be limited by the Vweight of jaw 4c.

Hence this part may desirably be made of fduralumin or similar aluminum alloy.

its it is'desired to make the locked posiion the normal position, l mayV provide a t bell crank lever 31, mounted on pivot 32 and tensioned in the proper direction by spring lt will be remembered that invthis normal locked position, the worm sleeveinay oe adjusted by hand operation after the manner of the ordinary monkey wrench.

he unlocled position of cam plug 25 is shown in Fig. ll, and the locked position in Figs. 2 and 7. Said plug 25 is rotatably mounted and the locking screw 28 is provided for the purpose of permitting adjustment and locking thereof either to the position of nig. if', the result of which is to re verse the diicction of pressures which will lock or unlock; or to the position of Fig. 5 and 6 wherein the cam is altogether inoperative because the lower end of the pilot screw is bevelled off as at 7a so that the cam swings by without contacting and the pilot screw remains in the lowermost position no matter which way the handle is stressed. In the latter position the jaw Ll may be adjusted by hand rotation of worm 3as above described. Y i

The various positions of cam plug 25 may be enteriorly indicated by pointer 25a.

The main function, so far as above described, would be performed, even if sleeves 10 and 3 were integral. An important feature, however, is making them separate and splining sleeve 8 on sleeve 10, as above described. p

In the specific arrangement shown in Fig. 2, the inner or pilot sleeve 10 is provided with ball bearings to eliminate frictional resistance to rotation. rlhe upper bearing is afforded by balls 35, in race 36, having an internal retaining lip 37, the function of which latter is mainly to prevent the balls from falling out, particularly while lthe parts are being assembled. rlhe lower bearincs comprise balls 88 in siinilarrace in the lower end of the sleeve 10, the other Abearing surface for the lower balls being the annulus 23 previously mentioned. Obviously, if the sleeve 10 were integral with locking sleeve 3,

these balls would have to take the full thrust of the maximum strains that can be applied on the sliding l and in practice these strains would be likely to exceed the crushing resistance of any balls suitable for use in such a position. Hence one feature of invention and advantage involved in making the locking sleeve 3 capable of slight longitudinal movement with respect to pilot sleeve 10, is that it permits the solid thrust surface lle to take the load and relieve the balls of all load. An incidental advantage is that the friction ofsurface le at the end of sleeve 3 becomes available as part of the friction lock factor, making it possible to use a locking thread 1 vof steeper pitch than would otherwise be possible; this in turn making it easier to get a slip angle pilotscrew of the same pitch as the locking thread. y

The spline connection 11, 12, leaves the sliding jaw 4 and the inner pilot sleeve 10 free for a slivht endwise movement with re- 'spect to the outer locking sleeve 3, when the pilot thread 8 rotates in locking thread 1, into or out of locking engagement with the rack teeth 2. Upon unlocking, when the pilot screw 7 is given its endwise, forward move ment, it thereby rotates the inner sleeve 10, spline 11, and the outer sleeve 3, to free the locking threads 1 from engagement with the rack 2, whereupon, the spline connection permits the outer sleeve 3 immediately to fall free from its frictional end-thrust engagement with surface Llc on the sliding jaw el. Upon locking, when the pilot screw 8 retreats endwise, its first effect is to take up the back lash in its own thread; then, to rotate the inn-er and outer sleeves to bring the locking thread into engagement with the rack teeth; and. thereafter upon further rotation the spline permits the locking thread to take out its own Vback lash by screwing itself valong vthe rack 2, into Vfirm engagement with surface 4C on said sliding jaw 4, thereby affording -a solidV path of thrust from the sliding jaw through the outer or locking sleeve and thread, to the relatively stationary rack, without endwise stress upon the inner sleeve.

When the retreat of the pilot screw is by spring pressure, the automatic' elimination i of all back-lash presupposes a. spring strong enough to do the work, which may not be ynecessary or desirable,V in certain cases.

Preferably the clearance between pilot thread elements 8 and 9, that is, back-lash or looseness of fit measured `lengthwise ot the pilot screw, is less than the clearance between the locking thread elements l and 2, in which case the pilot screw will take the load and will permit free sliding ot" the aw 4 in both directions. As considerable back-lash is unavoidable in the pilot screw because of the acuteness ot angle along which back-lash is measured, I prefer to make the pilot screw one of its working surfaces in position to take load and unlock thelocking screw.

In such case, the pilot screw maybe held to a midway position where it is inoperative and the lockingl screw locks against thrust in both directions; or by shifting one way orfthe ther, there will be sliding in one direction and lock in the other, but there is no position permitting tree sliding in both directions.

The inner sleeve l() is held in axial alignment with its thrust bearing by sleeve 3 ot which reduced portion 40 has sliding` lit within a recess in sliding jaw 4. At the other end sleeve 3 has an interior bearing 41 and ipple 24 and a washer 42 prevents longitudinal displacement of the reduced portion 40 out of its bearing. I

In all the foregoing, the pilot screw never has to sustain any important endwise thrust;

hence it can be made quite small, to give a high pitch toits thread on a limited predetermined number ot turnsl per-inch. Nevertheless, in practice, it ma i he desirable to cut the pilot groove quite close to the axis, in order to get the desired easy slip angle, where the locking thread is of particularlylow pitch. Hence, as shown in Fig. 3, I Vprefer to employ n, niiet screw ot substantial diameter and Figs. l to 7.

form the pilotthread as a groove cut in as close to the axis as maybe. necessary for the V,purpose in view, the outer portion ot the groove being cut away as at 8a, sothat only the inner portion 8 functions as a screw thread.

The pilot screw 7 and encircling spring 2l are preterablyprotected by tube 44, rigidly screwed tothe slidingl jaw bracket 4d and having-loose sliding t in illerpiece 45, secured in handle 13 by lugs 46.

`While the various details of my invention above-described as embodied in this type of monkey wrench are novel and are of cousiderable practical importance, all except the more basicteatures of function and'lconstruction are capable of wide variation as will he evident from the'forms hereinafter described. In some of these the similar shapes and struc-- tures will be obvious while in others they are shiftedV about and combined with new velements making identilicationsfmore diiiicult.

In Figs. 8, 9, and l0, the broad essentials ot the invention areappliedto vanother torni ot' monkey wrench; the external appearance-is that ot another well-known commercial form.

The basic elements and their co-operating functions areessentially identical with those Just described in detail in connection with features, and except for the diiierences which I Shall now describe, the preceding Ageneral statements `with .reference .to my `first described form of wrench may he taken .as

applying to the various embodiments described hereafter.

In'Fig. 8 the similar basic elements are the locking threads 5l on rotatable sleeve 5S, and the ,locking thread element 52 on a member which is longitudinally movable with respect to vthe sleeve g, also the pilot screw 57 with slip-angle groove 5S, engaging interior slipthreadelenients in said rotatable sleeve 53; also the spring 71 whichl has the double function of pressing the lower jaw 54 to the closed position `and also `forcing the pilot screw to inoperative position when the endwise thrust ,of the operating cam 65 is removed. The

shank 55, integral fixed jaw56 and the sliding jaw 54, with strap or loop members for retaining it in engagement with shank will also be recognized. An important practical dierence is that the handle is solid, has no oscillating movement, and may be shaped precisely according to the old standardized designs. In Fig. 8, the rotating locking-screw element 5l, 53, is now associated with the tiXed jaw and shank 55,'being rotatably mounted thereon in a step bearing 54C, and retained against withdrawal by knurled flange element 54", extending under projection 54d on shank 55. This rotatable locking screw element 5l, 53, is elongated to the Jiull length of the throw of the slidable jaw54, while the non-rotatable lockf Insofar as concerns genericA ing screw 52 is short, just the reverse of the length relations of the rack 2 and the worm l in Figs. l and 2; and said rotary locking element 5l, 53, is now associated with and carried by the sliding jaw element. Said pilot screw is held from rotation while being permitted the required longitudinal movement by guide sleeve 72, having a slot IO engaged by spline pin which passes through the rear end of the pilot screw. The sleeve T2 is screw threaded'into the sliding jaw and is locled in place by key screw 68.

The handle being rigid in Fig. 8, other` movable means must be provided for giving the pilot screw 57 the required endwise shift to throw it into lockino or unlocking position. The cam surface for performing this function is formed on a separate jaw-face element 80, the upper face of whichforins the work-engaging face of the sliding jaw. rlhis supplemental, working-face element of the .elf g jawis preferably the full width of the jaw. It is knurled at the sides as 'at 8l to afford a good holding grip whereby it may be moved transversely byhand to throw the cam surface 65 into and out of the displacing position at the rear end of the pilot screw 5". rlhe slidable face piece 8O is formed l with dove-tailed portion 32 depending into a correspondingly shaped recess inthe sliding jaw. The face piece, being inserted in the sliding jaw before assembling, is then safe from sliding out at the front. The slidable facepiece is also provided with a recess 83 for holding one end of a thrust spring 85, the end of which butts against a suitable surface on the slidable jaw at 84.

The spring .71 bears at one end on the bottom of recess Tlf* in the handle of the wrench and at the other end upon a collar 86 swivelled on the end of pilot screw 57. `The pressure of the spring on this collar has the primary effect of forcing the pilot screw as far back as the ca n will let it go and thereafter the further effect of pressing the slidable jaw to the closed posit-ion. Obviously, the slidable falce piece 8O may be pulled out or pushed in by hand the distance necessary to give the endwise cam thrust and retreat of the pilot screw 57, which will put it into and out of unlocking relation with the locking screw 5l.

rlhere is, however, a further and more impor ant capability of operation. When the jaws are open and aA nut of ordinary dimensions i, clamped between them, with its centreat a point indicated as at C, Fig. 8; then a rotary effort on the handle in the direction of the arrow lwill give a stress on slidl face piece 8O in the direction of arrow horizontal component of which, as d by arrow lvl, ten Ls to force such Ymen;` to the right moving' cam 65 rection for releasing and permitting tive position, thereby causing the locking thread 51 to lock the sliding jaw against opening.A Reverse pressure, however, applies a reverse sliding component to face piece 80, forcing cam 65 under the pilot screw 57, thereby thrusting the latter downward to cause rotation and unlocking of thelocking screw. Hence, this device will automatically lock and unlock in. response to alternate pressures applied on the handle; and will ratchet around and hug a nut or bolt head, as in Figs. l and 2;'but the cause will be the reversals stress and movement ofthe jaw face by the reversing pressures `on the nut, instead of pivotal movements of the handle.

The spring 85 normally tends to keep the cam piece in the rearmost or unlocking position and whatever wedging ction there is by the pilot screw 57 under the pressure of screw 7l, affords a further pressure in the same dircction. Under certain conditions, however, a tension spring such as the spring 185 of Fig. l1 may be substituted fortlie spring 85 in which instance, it would be `easier for the jaw 30 to slide outward and overcome the excess pressure of spring 7l and the bcdof the'face piece S() would be slightly inclined to give said face piece a pressure-responsive bias toward either :the locked or the unlocked position of same.

For convenience in manufacture and assembly, and also for the functional advantages, the jaw 56 and the shank 55 may be integral, the lower portion 55Ct being shaped` to lit the hand. Portions 55, 55a, will be small enough to pass through the straps 54a, 54h, ofthe sliding jaw, which` latter will be applied thereover after the face piece 80, with backin spring 85, have been inserted therein from the rear. rl`he locking screw sleeve 53 may be then screwed into 52 just `far enough to give the member 54X aloose ht against 54d when the jaws are closed. Thereupon the supplemental handle section 55h is applied and secured by screw lbolts 55C. The section 551 is additionally secured against the endwise strain by means of the endwise thrust shoulder 55d.

lt will be noted that in this device the locking' sleeve 53 taires the entire endwise load over the sliding aw, but its permissibly great diameter and tubular form well adapt it for sustaining such thrust. .There is, of course, no load on the pilot screw except that necessary to rotate locking sleeve 53 at a time when the latter is relieved of its load.

ln 1l and i2, l have shown another rigid-handle embodiment of my invention as applied to an S type wrench, wherein the j aw o iening is present-ed outwardly endwise of the handle. ln this form, certain features are so substantially like some of the parts in Fig. 2 that l have git/'en them the same numerals, while others are similar in function more than in form. The locking threads 1 are on the eX- CHS .terior of sleeve 3 which is movable longitudinally butnot -cifrcumferentially on inner sleeve 10, having interior pilot screw ele- .inent-s), the driving connection being through spline screw 11, engaging vspline groove 12.

,In the present fornnln7 11, the inner sleeve 101s not rovided with ball bearmvs but the 'splineassociationwith locking-sleeve 3 relieves sleeve 10 of Aall endwise thrust exactly as described in connection with Fig. 2. The

.pilot'screw 107 has the same functions as in .both the preceding; forms while the sliding vjaw piece 180earriesa cam surface 125, adapt-- ed to endwise shift the pilot screw to release the locking'. thread 1. rlhere is also a spring 121tending to close the"movable ]aw 104 a-.Ofainet the tiXed. `aw.1()6. and also to t irust .the pilot screw against the slidable cam surface125.

The pilot screw .element 107 is functional- "ly associated with'the slidable v and its endwise movement is controlled byand fron said jaw, although said pilot-screw element is. actually housed inthe ixedjaw member.

This, is made possible by use of pilot screw rod or extension member 12'?, slidably mounted the sliding` jaw N104i', and having a deendino' ortion 128 the lower end of which is secured to therear end of the pilot screw element, preferably by pivot 129.y The device'further differs from vany of the preceding in that the rack 102 is .on the slidable jaw.

-wherein spring 85 acts in harmony with spring 71. Consequently spring 185 mustrbe substantially weaker than spring'121, and its purpose is to make the face piece`180 more sensitive to unlocking` efforts.

.ln Fig. 11, as in Fig. 8, the locking screw vcan `always be rotated byhand even when the pilot screw is in the position for locking. n

In all the forms shown in Figs. 1 to 13, inclusive, the strength, proportion and arrangement of the parts is designedV with a vview to performing the unlocking operation at a time when the load is removed/or m mized on the sliding jaw, as by relief or reversal of pressure on the handle. rlhe broad principles of my invention, however, are applicable to devices wherein the load on the slidable member is continuous and very heavy. In such case, the relative movementof parts necessary for unlockingmight 'be by sufficiently powerful endwise thrust applied on the pilot screw. Preferably, however, the shift of phase between the locking thread and the pilot thread is accomplished .by movement of some other one or more of the two pairs of thread elements, one expedient being provision for slight relative rotation of the otherwise non-rotatable member .that is, va member corresponding to the rack in .F-igs. 1, 2 and 11 and corresponding` to the thread 52 in Fig. 8.

In this application I have described the pilot element as being a screw having same pitch as the locking,u screw element and adapted to rotate the locking screw element vat the proper rate of speed, while the latter is either in partial contact or entirely lout of contact with its co-operating locking member; but my invention in its broadest peet contemplates a mechanical movement broadly comprisingv locking members, a pilot member for controlling the state of lock or unlock, by its ability to rotate the locking member ata definite rate of speed, and means for positively shifting the phase relation of the locking' and pilot members whereby the degree of frictional Contact may be varied. at

willand may be held constant for any period oftime. This will broadly include the same or different forms of locking members, preferably toothed, and a different form of pilot .mechanism which may include toothed gearing of the proper size, chain belts, or other .positive-ratio, inotiontransmitting` mechanism. Such combinations are perhaps more applicable to the field of change gear mechanism, variable intermittent mechanisms, stepless ratchets, and one specific disclosure as to these is shown and described in my copendving,- application Serial No. 376,342, tiled Qluly As previously brought out it is evident that the constructions described herein admit of considerable Inodilication, and that many apparently widely different embodiments can be made without departing from the invention; therefore, I do not wishA to be limited to the precise arrangements shown and described, which are intended to. be merely illustrative, but the scope .of the protection contemplated is to be taken from the appended claims, interpreted as broadly as is consistent with the prior art.

l claim:

1. A monkey wrench including a handle, a shank pivoted thereto for slight relative movement, said shank constituting a guide member and having a rack thereon, a jaw lined to the shank, movable thrust receiving jaw slidably mounted on the shank for movement parallel to the rack, a locking` worm rota ably mounted on the movable aw having its threads continuously in mesh with and loosely fitting,v between the teeth of the rack,

the

\ having the same lead, the wrench handle for a pilot screw having a slip thread coaxial with said looking threads and'engaging a slip thread element rotating with said locking worm, the slip threads and locking threads a cam associated with moving theslip thread endwise to rotate the out of engagement with the yrack and to a position where movement of the released movable jaw in either direction will cause the rotary slip thread element to rotate and thereby rotate the locking thread element without reengagement with the rack teeth.

2. A monkey wrench including a shank, a rackon the shank, a jaw movable on the shank, a locking worm on the movable jaw, in combination with a slip screw, carried by the shank of the wrench, having a slip thread of the same lead as the locking thread, and having cooperating slip` threadelements within the worm, and means for shifting the phase of the slip threads'relatively to the locking threads to rotate and unlock the worm and thereafter supporting said slip screw in said position jaw may be slidably forced in either direction without thereby re-engaging the locking threads.

Y 3.-A wrench including alxedjaw and shank provided with a rack, a'slidable ijaw mounted on the shank, anda worm carried by the slidable jaw with the rack in combination with means brought into or out of operation by pressure on the wrench lhandle to move the locking worm out of locking engagement with the rack, and to positively rotate it to prevent relocking during movements of the sliding jaw in either direction. Y

4. A Wrench including relativelyv fixed and slidable jaws and a locking thread adjusting' screw therefor, in combination with. means brought into and out of operation by reversal of working pressures on the wrench i to unlock and rotate the adjusting screw with its locking threads free from locking engagement. v

5. A wrench havinga relatively fixed jaw and shank and a cooperating slidable jaw; a

rack on the shank and a worm sleeve rotatably mounted in and carried by thel movable jaw with its threads loosely meshingbetween the teeth of the rack to afford substantial back lash in the direction of thrust, in combination with a slip screw, supported' from the shank, in parallelism with the rack 'and' having a slip thread of the same lead as, but less backlash than, .the locking thread; a cooperating slip thread element ina drive sleeve within and splinedto the worm sleeve, to permitrelative endwise movement and to afl-'ord independent paths of thrust, one -path through the worm sleeve and the rack, and one through the drive sleeve and the slip screw; means for endwiseshiftin'g' the slip locking worm thread v so that the movableand continuously meshed rotate the'locking screw out of locking screw to shift the phase of the slip threads relatively to the locking threads to cause the slip screwto take load to rotate and unlock the worm and for supporting said slip'screw in the .shifted position so that the movable jaw may be slidably forced in either direc-A tion without thereby re-engaging the locking threads. l

6. The combination specified by claim 5, with the further feature of means for continuously pressing the slidable jaw toward the fixed jaw. 1

7. rJhe combination specilied by claim 5,. and in which the endwiseshifts of the slip screw to lock or unlock is controlled by a member moving automatically upon reversing of the working pressure on the wrench.'

8. A wrench having a relatively fixed jaw,v a shank and a cooperating slidable jaw, a. handle pivoted for slight movement relative to the shank, a rack onthe shank and aworm sleeve rotatably mounted in and carried by the movable. jaw with its threads loosel meshing between the teeth of the rack to a ford substantial backlash in the direction of thrust, in combination with a slipv screw supported from. the shank in parallelism withl the rack andhaving a slip thread of the same lead as but fless backlash than the locking thread, a cooperating slip thread element in a drive sleeve, within and splined to the worm sleeve, to permit relative endwise movement and to afford independent paths of thrust, one path through the worm sleeve and the rack and one through the drive sleeve andthe slipscrew, means associated with the handle for endwise shifting theslip screw to shift the v,phase of the slip threads relatively to thel locking threads to cause the slip screw to take load torotate and unlock the worm andA for supporting the slip screw in shifted p0- sition so that the movable jaw may be slidably forced in either direction without thereby re-engaging the locking threads.

n automatic ratchet wrench, yhaving relatively movable jaws, a spring for pressing the jaws into engagement, a locking screw for locking said jaws against opening under stress, in combination withl means operated by reversal of pressures onrthe wrench to automaticallyrotate the locking screw `out of locking frictional engagement `with its cooperating thread element, and for rotating said locking screw by and in accordance with endwise movement of the thus freed movable jaw at the rate required to prevent relooking engagement ofthe locking threads.

p l0. An automatic ratchet wrench, including cooperating relatively movable jaws, a springA for pressing rthem to closed position, a locking screw for the movable jaw, in combination `with` means for operating by reversed `working pressure on the wrench to engagement and to screw thesame at therate shank when working pressures are exerted engagement required to prevent relooking, during openingof the 4jaws of the wrench to rotate around the work and closing of the same by the pressure of said spring. c

11. The combination specified by claim 8 and wherein the wrench handle is pivoted on the shank to oscillate under the working pressures to move the locking worm. v

12., The combination specified by claim 3 and wherein the wrench handle is a. sheath surrounding and pivotally connected to the shank and adapted to come in solid contact therewith at the limit of movement under the working pressure thereby preventing a strain on the pivot. v 13. A wrench including a fixed jaw ,and a shank provided with a rack, a handle pivoted on the the shank to oscillate under working pressures, a slidable jaw mounted on the f shank, a worm carried by the slidable jaw and continuously meshed with the rack, in combination with means brought into -or out of operation ybya .pressure on the khandle to move :the lo king wormV out .of locking engagement with the rack and to positively rotate :it to V preventrelooking during :the movements of .the ysliding jaw in said handle contacting solidly with the shank when working pressures :are eXer-tedthereon.

14. A wrench including a ,fixed jaw and a shank provided 'with .a rack, a handle pivoted on the shank to oscillate under lworking pressuresfa slidable aw mounted on the shank, a worm carried by the slidable jaw and continuouslyfmeshed with the rack iii-.combination with means brought into or out of yoperationby a pressure onthe handle to move the locking worm out of. locking engagement with the rack and to positively yrotate it to prevent relooking during movements ,of the said handle.

sli-.ding jaw in either direction, contacting solidly iwith the shank when working pressures are exerted thereon, and a spring normally pressing the handle into with the shank.

L1A wrench including a fixed jaw anda shank provided with -a rack, .a handle pivoted'on the shank to oscillate under working pressures, a slidable jawmounted on the shank, a worm carried by the slidable jaw Y and `continuously meshed with the rack in combination with means brought into Vor out. of'operation by la pressure on the handle .to molve the locln'ng worm Yout of locking engagement withthe rack and. to positively rotate it to prevent relooking during move-I ments of the lsliding jaw in 'either direction,

said handle` contacting sol-idly with the thereon, a -spring normally pressing the handle into engagement with the shank, and a spring pressing the movable jaw toward closed position. y Y Y Vi6. The combina-tion specified by claim 2, in Awhich the means for ,shiftingsthe .slip

Vtion without thereby re-engaging either.k direction,

screw is a cam carried by and moving with the hollow handle pivoted on the shank.

17. The combination specilied by claim 13 in which the means for shifting the slip screw is a reversible cam carried by and moving with :a hollow handle pivoted on the shank.

18. A monkey wrench including ya shank, a rack -on the shank, a jaw movable on the shank, a locking worm on the movable jaw, in combination with `a slip screw, carried by the shank of the wrench,having a slip thread of the same lead as the having cooperating slipv thread within the worm, and means for shitting the phase of the slip threads relatively to the locking threads to rotate and unlock the worm and thereafter supporting said pilot screw in said position so that the movable jaw may be slidably forced in either directhe locking threads, a hollow handle pivoted on the shank andmeans for shifting the slip screw including a reversible cam carried by the hollow handle, said cam being adjustable to an inoperative position.

19.' A monkey wrench including a shank, a rack on the shank, a jaw movable on the shank, a locking worm on the movable jaw, in combination with a slip screw, carried by the shank of the wrench, having a slip thread of the same lead as the locking thread, and having cooperating slip thread elements within the worm, and means for shitting the phase tively to the locking threads to rotate and unlock the wormy and thereafter supporting said pilot screw in said position so that the movable jaw may direction without thereby re-engaging the locking threads, a hollow handle pivoted on the shank and means for shifting the slip screw including a reversible cam carried by the hollow handle, said cam being adjustable to an inoperative position, said cam being in the form of a rotatable plug having a shank projecting to the exterior and provided with an index indicating the Y*position of adjustment of thelcam.

elements v20. A wrench having a relatively fixed jaw and shank and a cooperating slidable jaw;

Va rack on the shank Yand a worm `sleeve rotatably mounted in and carried by the movable jaw with its threads loosely meshing between the teeth of the rack to afford substantial backlash in thedirection of thrust; in combination with aslip screw, supported from the shank in parallelism with the rack andhaving a slip thread of the same lead but less backlash than the 'locking thread; a

cooperating slip thread element within the worm sleeve; Vand means for endwise shift' ing .the slip screw to shift the hase of the slip threads relatively to the loc ring4 threads to cause the. slip screw locking thread, and

of the slip threads `relabe slidably forced in either to take thrust to ro tate and unlock the worm and for supporting said slip screw in the shifted position so that the movable aw may be slidably forced in either direction without thereby re-engaging the locking threads.

2l. The combination specified by claim 2O and a spring pressing the slip screw downward and the sliding jaw upward.

22. The combination specified by claim and wherein the slip screw extends into the handle and is protected by an encircling tube carried by the sliding aw.

23. A wrench having a relatively fixed jaw and shank and a cooperating slidable jaw; a

, rack on the shank and a worm sleeve rotatably mounted in and carried by the movable jaw with its threads loosely meshing between the teeth of the rack to afford substantialV sleeve; and means for endwise shifting the slip screw to shift the phase of the slip threads relatively to the locking threads to cause the slip screw to take thrust to rotate and unlock the worm and for supporting tf:- said slip screw in the shifted position so that the movable jaw may be slidably forced in either direction without thereby re-engagiig the locking threads, said slip screw extending into the handle and being protected by an encircling tube carried by the sliding jaw, and a spiral spring surrounding the slip screw within the tube, thrusting the screw downward and the sliding jaw upward.

24;. A wrench including a fixed jawl and shank, a relatively fixed thread elementa slidable jaw mounted on the shank, and a thread element carried by the slidable jaw and continuously meshed with the relatively fixed element, in combination with means brought into or out of operation by pressure on the wrench handle to move the thread elements out of locking engagement, and to positively rotate one of them to prevent relooking during movements of the sliding jaw in either direction.

25. A wrench including a lined jaw and a shank, a relatively fixed thread element, a handle pivoted on the shank to oscillate under working pressures, a slidable jaw mounted on the shank, and a thread element carried by the slidable jaw and continuously meshed with the relatively fixed element, in combination with means brought into or out of operation by a pressure on the handle to move the thread elements out of locking engagement, and to positively rotate one of them to prevent re-locking during movements of the sliding jaw in either direction.

26. A wrench including a lixed jaw and shank, a slidable jaw mounted on the shank and a continuously meshed locking thread adjusting screw therefor, in combination with means brought into or out of operation by pressure on the wrench handle to move the adjusting screw elements out of locking engagement and to positively rotate the adjusting screw to prevent re-locking during movements of the sliding jaw.

27. A wrench including a liked jaw and shank, a slidable aw mounted on the shank and a continuously meshed locking thread adjusting screw therefor, in combination with means movably mounted on the sliding jaw and automatically brought into or out of operation by pressure on the wrench handle and by the reaction of the corners of a nut held between the jaws, to move the adjusting screw elements out of locking engagement and to positively rotate the adjusting screw to prevent re-locking during movements of the sliding aw.

28. A11-automatic ratchet wrench including relatively movable jaws, continuously meshing threaded elements normally locking f said jaws against undesired opening, and means for pressing them to closed position, in combination with means for automatically rotating one of the threaded elements in response to thrust on the jaws, to permit opening and closing of'said jaws.

29. ln an automatic ratchet wrench adapt-ed for one hand operation, in combination, a fixed jaw, a relatively movable jaw, continuously meshing threaded elements normally locking said jaws against undesired opening, means for pressing said jaws to closed position, means for automatically shifting said threaded elements out of locking engagement and for then automatically rotating one of said elements in response to thrust on the jaws, to permit opening and closing said jaws, and linger grip means on said relatively movable jaws adapted for operation by a linger of the hand holding the wrench, for opening said jaws.

Signed, at New York city, in the county of New York and State of New York, this 14th day of February, A. D. 1931.

J ULIUS C. HOCHMAN. 

